Unit heater filter frame



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April 13, 1954 F. M. YOUNG 2,675,094

UNIT HEATER FILTER FRAME Filed NOV. 19, 1952 ATTORNEY Patented Apr. 13,1954 UNIT HEATER FILTER FRAME Fred M. Young, Racine, wis assignor toYoung Radiator Company, Racine, Wis., a corporation of WisconsinApplication November 19, 1952, Serial No.:321,434

This invention relates to fram structures for mounting removable filterson standard unit heaters.

Unit heater is the common designation for a type of overhead spaceheater eithersuspended from the ceiling or set on a'platform bracketedtoa side Wall. It Comprises a series of exteriorly finned tubes, throughwhich tubes a heated fluid flows, and wherewith is associated 'a fan fordirecting the heated air through thearea' between the fins forcirculation out into the room to be heated.

When this type of heater is used in plants where the equipment involvesthe use of viscous materials, which in the course'of their useinevitably contaminate-the a'tmesphere-ofthe room with atomized orvaporized particles thereof, the finned tubes of "th'ehea'ter in timebecome coated with concentrations of the viscous material. Obviously,these-accretions tendto reduce the heat exchange efficiency of theheater. 'Un'der extreme conditions this reduced efiicie'ncy'may be asgreat asfifty percent. Onlythe removal of this viscous coating willrestore the heater to its expected efiiclency.

Since these heaters are often suspended from a very high ceiling-orthe'wall platform is rather high above the floor-andthe *heat'ingcoilisconnected to the "heating fluid-inlet and outlet conduits, it is anexpensive operation to effect such cleaning. This is especially trueiftheheater'has to be disconnected and "lowered to the floor and thenormal operation of'the heating system interrupted. It, therefore,becomes advantageous to provide an eficient and economical arrangementfor associating filterswith -a unit heater and which will extract theseair-laden"deleterious materials before the air reaches the heatingcoils.

The main objects of this invention, therefore, are to provide animproved frame structure for mounting air filters on conventional orstandard unit heaters; to provide an improved filter frame structure ofthis kind which is simpl iii-"form, economical to manufacture, and easyto attach to the heating unit either before or after its installatureconstructed in accordance Withthis inVention, the filters "being showninplace; I

Claims. (01. 183--74) Fig. 2 is a similar view but showing the filtersremoved;

- Fig. 3 is a -horizontalsectional View taken on the plane of the line3-3 of "Fig. 1;

Fig. 4 is a vertical sectional view-taken on the plane of the line l4 ofFig. 3; and

Fig. 5 is an exploded view of the severaL'specially forlned partsconstituting a'p'articular embodiment of this invention.

The essential conceptof this invention involves the formation andassembly of a plurality ofparticularly-formed metal stampings forattachment to a unit heater housing seats to removably'support a pair ofstandard filters inangular relationship to each other rearwardlyoftheheater fan, and through which filters the air isdrawn before passingthrough -the heating coil.

A unit heater, for use "with which this filter frame structure isdesigned, comprises a housing 5 wherein ism'ounted-a finned-tube heatingcoil 7 and back of which is arranged a motor' driven fan 8.

The emlaodiment "of this concept shown in "the accompanying drawings,comprises apair of main mounting members II and l2, three spacingsupport elements 53,14, and '15, and a pair of bracing plates l hand ii, all of which'are bonded-together to form theiramestructure Withrectangular-side openings 16in front'of which'are supported the filterst3 the same being secured in position on the structure by 'a lockingplate 2t. As herein shown, all of these parts, constituting thisimproved structure, preferably are met-alstampings all, except thelocking plate, being spotwelde'd together.

The main mounting members 'II and I2 are of irregular hexagonal shapethree sides of which define rectangular'base'section 22 and-the otherthree sides defineatrapeziform'extension 23. The perimetrical portionsalong the short lease section sides and the non-parallel sides of thetrapeziform extension are bent over to provide transverse flanges 2t.Opposed and parallel to each of these flanges along the extension 23 isan angle bar 25 bonded to the inner races of'the respective members itand '12 to form guideways 26 for the filters E9.

The spacing support elements i 3 and I4 in cross section approximate a'2 one leg 21 of which is considerably longer than the other and"termimates in a flange 22!. These elements 1'3 and H are bonded attheir ends to the members II and 82 adjacent the basecorners. The shortleg 29 is disposed in alinementwith *the angle bars 25. The intermediatepart 3! forms an abutment at :xtheiend of the 'guideway 2'55 for afilter l9.

The spacing support element 15 in cross. section is somewhat channelshaped being formed by a web part 32 and divergent flanges 33. ,The webpart 32 of this element [5 in width is somewhat less than the short sideof the trapeziform extension 23. The element I5 is bonded at its ends tothe respectively opposed inner faces of the members H and I2 slightlyinward from the end of the extension 23 so as to dispose the flanges 33in alinement with the angle bars 25, thus aiding in defining theguideways 26.

The bracing plates l6 are of right angle triangular form with integralflanges 30 formed along the right angle edges. These bracing plates itare set medially at the juncture of the spacing support element I5 andthe members H and I2 and disposed rearwardly toward the respective basesections 22. The plates 16 are secured in this bracing position byhaving the flanges spot-welded to the element l5 and the members! I and[2.

The filter locking plate 2| in cross section approximates the form ofthe element l5 except the web part 34 is slightly wider than the webpart 32 of the element l5. A pair of bolts 35, extending throughapertures in the web parts of the element !5 and the plate 2|, withtheir winged nuts 36, hold the plate 2| with the flanges 31 against thefilters l9 and serve to lock them in the guideways 26 to cover theopenings 18. (See The base sections 22 of the members II and I2 haveapertures 38 formed therein along the rear edges whereby suitablefastening means -such as bolts and nuts-may be used to secure thestructure to the housing 6 of the unit heater with the flanges 28abutting the heater housing 6/ The lower member I2 is provided with aninsulating grommet 39 through which the electric wires lead to the unitheater motor. With a filter frame structure of this kind. the

' standard unit heater, when used in plants where the air iscontaminated with atomized or vaporized viscous materials, can bequickly and economically equipped with filters to protect the heatingcoils from acquiring an insulation of these viscous materials to thedetriment of its proper functioning. Moreover, such a frame structurepermits the filters to be readily removed for cleaning-or thrownaway-and replaced without removing the unit heater or in anyway'disturbing the heating system.

I claim:

1. A filter frame structure for unit heaters comprising, a pair ofspaced members each comprising, a pair of members with trapeziformsections, transverse supporting elements bonded at their ends to themembers adjacent the corners of their respective bases and adjacent theopposite parallel edges for disposing the members in spaced parallelrelationship to constitute rectangular openings along the non-parallelsides of the members and along the bases thereof,

means for attaching the members along their respective bases to theopposite sides of a unit heater housing, and flanges arranged along thenon-parallel edges of the members to constitute guideways for theinsertion and removal of standard filters to close the rectangular sideopenings.

3. A filter frame structure for unit heaters comprising, a pair ofmembers with trapeziform sections the non-parallel perimetrical portionsof which are bent to form transverse flanges, transverse supportingelements bonded at their ends to the members adjacent the oppositeparallel edges for disposing the members in spaced parallel relationshipto constitute rectangular openings along the non-parallel sides of themembers and along the bases thereof, the elements adjacent the base incross section approximating a Z and disposed with one leg inwardlyparallel to the respective member flanges, the other element in crosssection being channel-shaped and secured adjacent the opposite paralleledges of the members, angle bars bonded to the opposed faces of themembers in alinement with the one leg of the respective Z-shapedelements and with the flanges of the channel-shaped element so as tocoact with the member flanges to form guideways for the insertion andremoval of standard filters to close the rectangular side openings, andmeans for attaching the members along their bases to the opposite sidesof a unit heater housing.

4. A filter frame structure for unit heaters comprising, a pair ofmembers with trapeziform sections the non-parallel perimetrical portionsof which are bent to form transverse flanges, transverse supportingelements bonded at their ends to the members adjacent the oppositeparallel edges for disposing the members in spaced parallel relationshipto constitute rectangular openings along the non-parallel sides of themembers and along the bases thereof, the elements adjacent the base incross section approximating a Z and disposed with one leg inwardlyparallel to the respective member flanges, the other element in crosssection being channel-shaped and secured adjacent the opposite paralleledges of the members, angle bars bonded to the opposed faces of themembers in alinement with the one leg of the respective Z-shapedelements and with the flanges of the channel-shaped element so as tocoact with the member flanges to form guideways for the insertion andremoval of standard filters to close the rectangular side openings, aright angle triangular brace flanged along its right angle edges bondedmedially to the inner faces of each of the members and the otherelement, and means for attaching the members along their bases to theopposite sides of a unit heater housing.

5. A filter frame structure for unit heaters comprising, a pair ofmembers with trapeziform sections the non-parallel perimetrical portionsof which are bent to form transverse flanges, transverse supportingelements bonded at their ends to the members adjacent the oppositeparallel edges for disposing the members in spaced parallel relationshipto constitute rectangular openings along the non-parallel sides of themembers and along thebases thereof, the elements adjacent the base in"cross section approximating a Z and disposed with one leg inwardlyparallel to the respective member flanges, the other element in crosssection being channel-shaped and secured adjacent the opposite paralleledges. of

the members angle bars bonded to the opposed faces of the members inalinement with the one leg of the respective Z-shaped elements and withthe flanges of the channel-shaped element so as to coact with the memberflanges to form guide- Ways for the insertion and removal of standardfilters to close the rectangular side openings, at channel-shapedlocking plate of cross section similar to the other element, means forremovably attaching the locking plate to the other element to secure thefilters in position in the guideways, and means for attaching themembers along their bases to the opposite sides of a unit heaterhousing.

References Cited in the file of this patent UNITED STATES PATENTS

